On 06/27/2017 08:44 AM, Christoph Hellwig wrote:

On Tue, Jun 27, 2017 at 08:16:49AM -0600, Jens Axboe wrote:

quoted

But we have to handle it, not doing so would be fragile. So our
options are:

1) Keep the stream_mappings[] array. It's simple, and it'll work
   for any number of streams.

2) Kill stream_mappings[] and just do the MOD again.

3) print a message and tell streams aren't supported on this device.

Is that your nvme preference - if less than 4 streams, just ignore it?
Would seem a shame to lose out with 2 streams, I can think of several
hot/cold scenarios that would probably work fine with that. But at the
same time, not a big deal to me, if you prefer just turning it off
for < 4 streams, that's fine with me.

-- 
Jens Axboe